Not sure about big power but I made 156.7 rwkws with hondata, 72mm throttle body port matched IM, mugen v1 intake, toda header, 70mm test pipe, ASM 70 SS exhaust.
Id also be concerned with resale and maintenance, if you plan on keeping at car 5-10 years with an average of 15k kms a year (min) it will have well over 300k kms on it when it comes time to sell....
I have done it twice and its approx $700, im pretty sure thats with new bearingsand seals each time though. A mechanice removes it and generally sends it off to a diff specialist.
Correct, Australian AP2 has seam welded upper arms not spot welded, stronger diff casing, carbon synchros, AP2 rear subframe with revised geometry etc. its everything bar F22c
He over quotes on the website and refunds you the difference. I just bought two CR wings and paid 750 u.s postage, but got refunded 200 u.s in shipping once he sent it.